Large presses are well known for making large items such as automobile components by pressing a metal blank. Typically, such presses include a press body and a pressing apparatus for pressing a metallic blank inserted intermediate the pressing apparatus and a die set positioned on a bolster. It is a continuing problem in this art to provide a means for changing the die sets in the press when the die sets are positioned on a moving bolster.
A typical die set utilizes a moving bolster to assist in the movement and positioning of the die set within the press. For a die set change, the bolster supporting the existing die set is withdrawn from the press. Thereafter, a second bolster supporting a second die set is moved into position within the press and secured at that point.
The productivity of a press is directly related to the amount of operating time for the press, and thus the number of pieces that the press produces. One factor which has reduced the operating time for the press has been the change in the manufacturing community to a "just in time" supply system. The manufacturing community has been moving toward and is now demanding that suppliers operate under a "just in time" supply environment. While large numbers of a particular part can be pressed from a single die set before requiring changing of die sets due to die wear, the "just in time" supply environment requires fewer parts to be made before a die set change is required to manufacture a different component and not because of excessive die wear.
"Just in time" supply requirements have thus increased the frequency of die set changes due to the minimization of inventory of a particular part due to cost reasons. The increased frequency of die set changes has decreased the productivity of the presses due to the idle time when die set changes are being made. Thus it is desirable to move the bolsters supporting the die sets as quickly as possible, while avoiding damage to the equipment for failing to stop the die sets adequately given the large size and weight of these die sets.
While various prior art systems have been developed which are directed towards increasing the speed and efficiency of die changes, continued development of moving bolsters and systems for moving the bolsters are directed towards a simpler and more efficient apparatus and system for making die set changes.